More than 1 million people gathered in Washington and in cities around the country and the world Saturday to mount a roaring rejoinder to the inauguration of President Trump. What started as a Facebook post by a Hawaii retiree became an unprecedented international rebuke of a new president that packed cities large and small — from London to Los Angeles, Paris to Park City, Utah, Miami to Melbourne, Australia.

The organizers of the Women’s March on Washington, who originally sought a permit for a gathering of 200,000, said Saturday that as many as half a million people participated. On Sunday, Metro officials announced that Saturday was the second-busiest day in the Washington subway system’s history, with 1,001,613 trips. (By contrast, on Trump’s Inauguration Day, the system recorded 570,557 trips.)

Many in the nation’s capital and other cities said they were inspired to join because of Trump’s divisive campaign and his disparagement of women, minorities and immigrants. In signs and shouts, they mocked what they characterized as Trump’s lewd language and sexist demeanor.

The marches provided a balm for those eager to immerse themselves in a like-minded sea of citizens who shared their anxiety and disappointment after Democrat Hillary Clinton’s historic bid for the presidency ended in defeat.

“We just want to make sure that we’re heard,” said Mona Osuchukwu, 27, a D.C. native. “I want her to know that she has a voice,” she said of her 3-year-old daughter, Chioma, who was with her at the march. “No matter what anyone tells her, especially as a black woman in America.”

The Washington demonstration was amplified by gatherings around the world, with march organizers listing more than 670 events nationwide and overseas in cities including Tel Aviv, Barcelona, Mexico City, Berlin and Yellowknife in Canada’s Northwest Territories, where the temperature was 6 degrees below zero.

In Chicago, the demonstration was overwhelmed by its own size, after 150,000 demonstrators swamped downtown blocks. It forcedofficials to curtail their planned march, although thousand of protesters still paraded around the Loop. In Boston, police estimated a gathering of 125,000. In Los Angeles, officials temporarily closed some side streets to accommodate the crowds.

“We are doing our best to facilitate, because they are squeezing into every street right now,” said Capt. Andrew Neiman of the Los Angeles Police Department.

New York, Miami, Denver and Seattle also had huge gatherings.

In Juneau, Alaska, one man marveled that the crowd was the biggest he had ever seen on the state Capitol’s steps. In Philadelphia, marchers filled city bridges. In Lexington, Ky., they shut down streets. In New Orleans, participants played brass instruments.

On Sunday morning, President Trump fired back on Twitter: “Watched protests yesterday but was under the impression that we just had an election! Why didn't these people vote? Celebs hurt cause badly.” Later, he tweeted a more conciliatory take on the marches. “Peaceful protests are a hallmark of our democracy. Even if I don’t always agree, I recognize the rights of people to express their views.”

The fear — and anger — about Trump’s rise to the most powerful position in the United States reverberated at renowned protest sites around the world, from the Trocadero in Paris to Trafalgar Square in London.

Marina Knight, a 43-year-old executive assistant, and her 9-year-old daughter were two of the tens of thousands marching in London.

“This is her first march,” Knight said, referring to her daughter. “It’s the first time we felt it was vital to march. I feel the rights we take for granted could go backward, and we owe it to our daughters and the next generation to fix this somehow.”

In the United States, the crowds marched in weather ranging from balmy to snowy. But common to every gathering was fiery rhetoric, pink knit hats and repeated references to the boast that offended so many women: Trump’s infamous taped comments in 2005 about groping women’s genitals.

Among the thousands of signs that marchers dumped at the end of the day in front of the Trump International Hotel, just blocks from his new home at 1600 Pennsylvania Ave.: “P---y Power” and “This P---y Bites Back.” Protesters got as close as they could to the presidential mansion, crowding metal barriers less than a block away as police and Secret Service personnel watched closely.

Demonstrators came to Washington from around the country, sometimes sleeping on the couches of people they had never met. They choked Metro stations as they made their way to the protest. The city issued about 1,800 bus parking permits for the march, and Amtrak added extra trains in and out of Union Station.

The huge crowd delighted iconic feminist Gloria Steinem, 82, who was among the first speakers. “This is the upside of the downside,” she exulted. “This is an outpouring of democracy like I’ve never seen in my very long life.”

Clinton did not attend the march but tweeted her gratitude: “Thanks for standing, speaking & marching for our values @womensmarch. Important as ever. I truly believe we’re always stronger together.”

The size of the gathering proved challenging. The audio from sound system did not reach everyone in the massive crowd, and far more portable toilets were needed.

When the toilets behind the stage broke down, security instructed women to use cups and ushered them into a box truck for privacy.

“I’m afraid to shake anyone’s hand,” one woman joked.

Although the marchers were mostly female and white, men and people of color also joined the throngs.

John Fischer, a 34-year-old locksmith from Grand Rapids, Mich., drove more than nine hours with his wife, Kara Eagle.

I’m here to support my wife,” Fischer said. “I don’t care who you are, women impact your life, and there’s no reason why they shouldn’t have the same rights as men.”

Cynthia English, a 61-year-old Jamaican American who lives in Florida, said she wants the new president to know that women will be fighting during his presidency to ensure that the country and laws treat them equally. She was with her daughter and marching for her two granddaughters in the hope that no future president feels comfortable making lewd comments about women.

“I don’t want this to happen to them 20 years from now, so I am making my mark now,” said English, who wondered, “Why are we the ones that bring people into this world, and we are treated the worst? We should be treated with respect.”

The crowd was buoyant, even joyous. Many held up signs — “I Am Very Upset!” and “Love Trumps Hate” and “Bridges Not Walls” — while others took videos of the experience on their cellphones. Every few minutes, a rolling roar swept over them.

D.C. police said they had made no march-related arrests, compared with more than 200 Friday when protesters created chaos in downtown Washington.

March organizers briefly considered suspending the formal march to the Ellipse out of concern that the crowd had grown too large to safely navigate the route to the White House. But speakers soon told the marchers to set out.

Lorraine LaHuta, 66, who came to the march from New York City, said that at times she wasn’t sure where to go, but that it never felt chaotic. “It was organized disorganization that worked very well,” she said.

Judith Snyder-Wagner, a 67-year-old former fundraising consultant, came because she sensed a shift in the rural, blue-collar community near Canton, Ohio, where she lives with her wife, Joy. A neighbor mowed a piece of grass along their property line and put up a Trump sign facing their home. Someone recently drove through the neighborhood flying a Confederate flag.

“We’ve been afraid,” she said, her voice quavering. She was limping up the sidewalk on Independence Avenue. She has had both her knee and hip replaced, and she held a cane in one hand and a poster in the other. “We just feel like we’re going to lose our civil rights.”

The couple boarded a bus at 1 a.m. Saturday in Ohio and would head home less than 24 hours later. “We needed to feel inspired,” Joy Snyder-Wagner said, looking around. “And we do.”

Trump’s election was the wake-up call that progressives needed, said Erin Edlow, 28, the membership director of the Virginia Beach Young Democrats. She was in town with her sister to demonstrate her support for the rights of immigrants and of lesbian, gay, bisexual and transgender people.

“Democracy is not a spectator sport,” Edlow said.

The march turned into a star-studded event, with celebrities such as Madonna, Janelle Monáe, Scarlett Johansson and Ashley Judd making appearances. D.C. Mayor Muriel E. Bowser (D) introduced herself as a proud “chick mayor” and implored the Republican majority in Congress to stop meddling in the District’s local lawmaking.

Activist filmmaker Michael Moore ripped a copy of The Washington Post in half, noting the headline “Trump takes power” and declaring, “I don’t think so.” Actress America Ferrera said that “our new president is waging a war” on the values that define the country with “a credo of hate fear and suspicion of one another.”

“It’s been a heart-rending time to be both a woman and an immigrant,” said Ferrera, whose parents are from Honduras. “Our dignity, our character, our rights have been under attack.”

“But the president is not America,” she said. “We are America.”

As the march grew in prominence, it highlighted long-existing racial and political rifts in the feminist movement. The initial organizers were white women — a group that narrowly voted for Trump in November — although they quickly handed its leadership over to a diverse group of longtime organizers from New York.

They have embraced an imperiled liberal agenda, in sharp contrast to much of what Trump laid out for his presidency. The march platform focused on issues such as workers’ rights, reproductive rights, environmental justice, immigrant rights, ending violence against women and more.

But a group of women who oppose abortion also came, beseeching the larger march to recognize their variety of feminism. Whether to include the conservative viewpoint sparked controversy in the days before the event. Antiabortion activists said they were excluded.

Siobhan Rooney, 32, drove from Philadelphia on Saturday morning to march for women’s rights. For her, that includes the rights of fetuses.

“We are in the same page on so many issues. It’s just this one issue,” she said.

Teresa Shook, who is in her 60s, was on hand to marvel at what emerged from her original proposal for a march in a November post on Facebook. The grandmother of four from outside Hono­lulu accepted hug and after hug as the crowd surged around her.

“This is the woman who came up with the idea for today’s march,” one woman said. “Thank you!” shouted another.